WASHINGTON (AP) — Vernon Hugh Bowman seems comfortable with the old way of doing things, right down to the rotary-dial telephone he said he was using in a conference call with reporters.

But the 75-year-old Indiana farmer figured out a way to benefit from a high-technology product — soybeans that are resistant to weed-killers — without always paying the high price that such genetically engineered seeds typically brought. So now he’s ignited a legal fight with seed-giant Monsanto Co. that has reached all the way to the Supreme Court, with argument taking place Tuesday.

The case poses the question of whether Bowman’s actions violated patent rights held by Monsanto, which developed soybean and other seeds that survive when farmers spray their fields with the company’s Roundup brand weed-killer. The seeds dominate American agriculture.